Laser modification of complex objects

ABSTRACT

An apparatus and method for perforating, cutting, or engraving a workpiece using a focused laser system to produce a focused laser. The apparatus includes a workpiece former having a complex shape to which the workpiece substantially conforms. The apparatus also includes a positioner that makes an adjustment to keep the focused laser substantially focused on the workpiece as the positional relationship between the workpiece former and the focused laser system changes to an operating position that changes the distance between the workpiece and the focused laser system due to the complex shape of the workpiece former.

REFERENCE TO RELATED APPLICATIONS

This application claims the benefit of U.S. Provisional PatentApplication No. 60/410,543, filed Sep. 13, 2002, the entirety of whichis hereby incorporated by reference.

BACKGROUND

1. Field of the Invention

The present invention is directed to cutting, engraving, or perforatingproducts by means of relative movement between the product and anoptical beam source.

2. Related Art

Current techniques for cutting and perforating flexible products such aslatex rubber gloves and garments involve inefficient manual laboroperations. For example, perforations can be made by includingprotrusions on a former and then abrading any dried latex that forms onthe protrusions.

Other techniques, such as mechanical piercing, are limited in both theirprecision, accuracy, and feature size. Furthermore, manual or purelymechanical techniques can be even more difficult and time consuming ifthe products must first be removed from the formers on which they aremade before processing. Thus, an improved method for quickly andprecisely cutting, perforating, and engraving flexible products isneeded.

SUMMARY

The present system provides fast, accurate, high density perforating,engraving or cutting of simply or complexly shaped products (such aslatex products). A target product is positioned on a carrier (such as abody mannequin or former). The former may be made of a variety ofmaterials such as metal (e.g. aluminum) or porcelain. The former and anoptical beam (such as a focused optical beam) are moved relative to oneanother (either by moving the former, moving the optical beam source,moving the focus, or moving two or all of these simultaneously) so theformer is in the proper position relative to the optical beam. Theoptical beam may then perforate, engrave, cut, or otherwise modify theproduct on the former. The perforations, engravings, or cuts to theproduct may be on any portion of the product (such as the front, back,or sides of the product).

BRIEF DESCRIPTION OF THE DRAWINGS

Exemplary embodiments of the present invention are described herein withreference to the drawings, in which:

FIG. 1 is a block diagram of one embodiment of the device;

FIG. 2 is a side view of a laser ray, a lens and a focal plane;

FIG. 3 is a side view of one example of a laser gun and motors;

FIG. 4 is a side view of the laser ray, lens and focal plane shown inFIG. 2 with a former in a first position and a second position; and

FIG. 5 is a perspective view of a medical glove on a former with a laserray and lens.

DETAILED DESCRIPTION

Preferred and alternative embodiments of the subject system and methodare described herein. The present invention will be described withrespect to certain embodiments and drawings. It will however be apparentto the person skilled in the art that other alternatives and equivalentsor embodiments of the invention or combinations thereof can be conceivedand reduced to practice without departing from the proper scope of theinvention as defined in the appended claims.

Referring to FIG. 1, there is shown a block diagram of the system. Acontroller 10 controls the operation of the system. Examples of acontroller include, but are not limited to, a computer, a terminal, aworkstation, or some other electronic device capable of controlling theoperation of the positioning device 16 and the optical beam device 24.The controller 10 includes a processor 12 and a memory 14. The processor12 may comprise a microprocessor, a microcontroller, or any device whichperforms arithmetic, logic or control operations. The memory 14 mayinclude non-volatile memory devices such as a ROM, or magnetic oroptical memory. The memory 14 may also include volatile memory devicessuch as a RAM device. Software may be included for the controller tocontrol components within the system, such as the positioning device 16and optical beam device 24.

The controller 10 communicates with the positioning device 16, asdescribed in more detail below. The positioning device 16 includes atleast one motor 18 for moving a former 22 (or alternatively moving theoptical beam device 24 or the focus of the optical beam device 24). Thepositioning device 16 further includes at least one sensor 20 forsensing the position of the former 22 (or alternatively sensing theposition of the optical beam device 24). In an alternate embodiment, thesensors may be located within the controller 10. In one embodiment, thepositioning device 16 may be a robotic device.

In order to work on the products, the products are preferably positionedon a carrier during perforation, engraving or cutting. The positioningof the product on the carrier enables the product to be given3-Dimensional proportions (rather than merely 2-Dimensional proportionssuch as by laying the product flat). In one aspect, the products may belatex rubber or any other elastic or stretchable item.

There is thus provided an apparatus in accordance with a preferredembodiment of the present invention which may include:

1. An optical ray source, optical beam array, split-ray source ormulti-ray source.

2. A positioning device comprising a distance determiner and sensors.

3. A product carrier such as a 3-Dimensional curved former.

A method for perforating and cutting may be performed as follows. Theformer 22 carries a product, and an optical beam device 24 may bepositioned relative to the former 22. In one embodiment, the former 22is positioned, by a positioning device 16 using motors 18, to a processstarting point where the distance and focus of the optical beam are inproper working position. The optical beam device 24 is capable ofperforating, cutting or engraving the product. In an alternateembodiment, the optical beam device 24 is positioned by the positioningdevice 16 to a process starting point. In still an alternate embodiment,both the former 22 and the optical beam device 24 may be positioned bythe positioning device 16. In one embodiment, the former 22 may comprisea mannequin. In one embodiment, the optical beam device 24 may comprisea CO₂ laser which is suitable for cutting or perforating materials.Other types of lasers may be used.

The optical beam device 24 may include a variety of controllableparameters. Examples of the parameters include, but are not limited to,intensity, duration, wavelength, focus and period of time. Theparameters of the optical beam may be operated in accordance with theproduct's characteristics such as material, color, thickness, and inaccordance with perforation specifications such as depth, width,dimensions, density, shape, pattern, etc. The parameters for operationof the optical beam may be set automatically or manually. If setautomatically, the parameters may be determined by accessing the memory14 which stores the parameters for operation of the optical beam.Alternatively, the optical beam may scan the product using a sensor orsensors (such as a sensor or sensors included with the positioningdevice 16) on the former to determine aspects of the product such asmaterial, thickness, color, etc. of the product. Based on thisdetermination, the memory 14 may be accessed to set the parameters forthe optical beam based on the aspects of the product.

After the first step of perforating or cutting, the positioning device16 preferably repositions the former 22 or the optical beam device 24,so that the new position on the former 22 is at the focus plane of theoptical beam from the optical beam device 24. In one embodiment, thepositioning device 16 moves or rotates the product on the former 22 infront of the optical beam device 24 according to data received from thedistance determiner (not shown) and the sensing system 20.

Alternatively, the positioning device 16 moves the optical beam device24. In another alternative embodiment, the positioning device 16 movesboth the former 22 and the optical beam device 24. As anotheralternative, the positioning device 16 can move one or more focusinglenses so that a workpiece on the former 22 is substantially at thefocus plane of the optical beam regardless of a change in the distancebetween the former 22 and the optical beam device 24.

The distance between the focal plane and the product and the focallength of the ray along the process can be pre-set for all the steps ofthe perforating process, for instance by mechanical routine, bysoftware, or by any other suitable method known in the art so thepositioning device 16 will correct the distance and focus during itsmovements along the production process.

Alternatively, the determination and adjustment of distance and focuscan be done in real-time by a measurement or sensing device, such as anoptical device, ultrasonic device (for example, the one or more sensors20 on the positioning device 16) or other devices known in the art, andthe data can be transferred to the controller 10 and to the positioningdevice 16 for appropriate adjustment of the location of the former 22 inrelation to the focal plane.

Referring to FIG. 2, there is shown a side view of a laser ray 26, alens 28 and a focal plane 30. The laser ray 26 may be focused onto afocal point 32 in the focal plane 30 using lens 28. Focusing the laserray 26 allows for better cutting, engraving or perforation. The focallength 34 may vary in distance and may be defined as the distance fromthe lens 28 to the focal plane 30. One example of a suitable focallength 34 distance is 100 millimeters.

Referring to FIG. 3, there is shown a side view of one example of a CO₂laser gun 36 and motors 18. The CO₂ laser gun 36 outputs a beam which isreflected by mirror assembly 38, which can be, for example, an X-Ysystem capable of scanning the laser ray 26 in two directions. Motors 18may drive mirrors in mirror assembly 38 in any direction, such as the xor y directions. This allows for the laser ray 26 reflected by mirrorassembly 38 to make particular traces, such as a circular trace 40, asshown in FIG. 3. In this manner, the laser ray 26 may be used to cut,perforate, or engrave certain shapes on the product that is on theformer 22. For example, a buttonhole may be cut by controlling the traceof the laser ray 26 so that it travels in a circular or elliptical path.Alternatively, the laser ray 26 may remain stationary and the former 22may move so that certain shapes may be cut on the product. In still analternate embodiment, both the laser ray 26 and the former 22 may bemoved relative to one another. In one embodiment, the lens 28 is locatedbetween the mirror assembly 38 and the former 22, although it ispossible for the lens 28 to be located between the CO₂ laser gun 36 andthe mirror assembly 38.

Referring to FIG. 4, there is shown a side view of the laser ray 26,lens 28 and focal plane 30 shown in FIG. 2 with the former 22 in a firstposition and a second position. The former 22 may be in a firstposition, with the laser ray 26 being focused on area 1 by lens 28. Asshown, an area 1 is in the focal plane 30. Further, the former 22 may bemoved (such as by rotating and moving the former 22 in the x, y or zdirections) so that a second area, such as an area 2 may be in the focalplane 30. In this manner, different sections of the product on theformer 22 may be subject to cutting, perforating, or engraving. In oneembodiment, the former 22 may be moved so that the laser ray 26 is in acertain area (such as one of the areas 1, 2 or 3). Within a certainarea, the laser ray 26 may be moved (such as by using the motors 18 asshown in FIG. 3). In this manner, rough adjustments as to where thelaser ray 26 hits the product may be performed by moving the former 22,while fine adjustments may be performed by moving the laser ray 26 (suchas by operating the mirror assembly 38). For example, if one seeks tocreate a series of small holes in a particular area, the former 22 maybe moved to an area (such as the area 1) and the laser ray 26 may bemoved to create a series of pinpoint holes (such as in a grid).

Referring to FIG. 5, there is shown a perspective view of a medicalglove on the former 22 with a laser ray 26 and lens 28. The former 22may be connected to a robotic device (which functions as the positioningdevice 16). The connection may be made by attaching pole 44 on theformer 22 to the robotic device. The former 22 may then be moved. Forexample, the former 22 may be dipped in a bath (such as a bath of latexliquid). The robotic device may hold former 22 within the bath for aperiod of time and then be withdrawn from the bath. After the latexliquid on the former 22 solidifies, the product on the former 22 may becut, engraved, or perforated. The robotic device may move the former 22in any direction and to any position so that the laser ray 26 maycontact any portion on the former 22. For example, to cut the opening ofthe medical glove (where the hand is inserted), the laser may remainstationary, focusing the laser ray 26 on an upper portion of the former22 (for example at a point 46) and the robot may move the former 22 in acircular direction so that the cut can be made along the circumferenceof the glove.

The system is thus suitable for cutting, perforating or engravingnon-flat surfaces, polygons, complicated 3D shapes, curved surfaces,asymmetric shapes, etc. and can be used with a wide range of targetmaterials, such as plastics, polymers, rubber, thin polymers layers,elastomers, metals, glass, and more.

One example of the operation of the system is as follows. An industrialrobot dips the former 22 in latex liquid, the former 22 is pulled up andthe former 22 is positioned by the motors 18 of the positioning device16 in front of the optical beam device 24 at such a distance that thefocus of the laser ray 26 will be accurate and most effective (e.g.,positioning the former 22 so that at least a portion of the former 22 isat the focal plane 30) to perforate a target area of the latex film onthe former 22. The focus of the laser ray 26 may also be adjusted togive optimal performance instead of, or in addition to changing thedistance between optical beam device 24 and the former 22.

The laser ray 26 may then be operated to perforate or cut the product,in accordance with the selected volume, wavelength focus and period oftime and in accordance with the product's characteristics as describedabove.

The former 22 may then be rotated and repositioned by the robot, so thatthe next area to be perforated is facing the ray source (such as at thefocal plane 30), at the same distance and at the same angle to the laserray 26.

If the former 22 shape is complicated, the robot may be required to makehorizontal, vertical, and rotation movements, in order to bring theformer 22 to the correct position in 3-Dimensional space relative to thelaser. Accordingly, the robot may be required to work in any number ofaxes.

The focus may also be readjusted and a second step of the perforationmay then be carried out within a very short time. These steps may berepeated, so that all the perforations and cutting required are finishedin a relatively short time.

The movement of the former 22 in front of the laser ray 26 can be donestep-by-step, or in the case of cutting, can be continuous and smooth,with all movements in all axes being done simultaneously, so that aclean cutting line will be formed.

It is also possible that the focus or distance of the optical laser ray26 from the former 22 may be adjusted during the movement of the former22. As a result, a hole, group of holes, cuts or engraving may becreated in the latex layer while the product is still on the former 22,with no need to remove the product and put it on another device forperforating. In this manner, there is no need to remove the product(such as latex garment) from the former 22 in order to cut/perforate theproduct (as was done in the prior art). Rather, the cutting,perforating, or engraving may be performed on the former 22 which isused to form the latex product.

It should also be appreciated that this system enables very high-densityperforation, where the distance between the holes and the size and shapeof the holes are virtually unrestricted and the location and shape ofthe holes and cuts are very accurate. Further, the edge finish usingthis system and method is clean.

The method may thus be used to create perforations, in order to makeaeration areas, lighted areas, patterns and designs, buttonholes, laceholes, tearing lines, etc. The method may also be used to cut aproduct's edges, to engrave patterns, or for any other purpose.

Latex products can be gloves, garments, dressings, other body relatedproducts, industrial products, or any other products.

Several embodiments of the present invention have been described herein.It is to be understood, however, that changes and modifications may bemade in these described embodiments without departing from the truescope of the invention, which is defined by the following claims.

1. An apparatus for modifying a workpiece, the apparatus comprising: afocused laser system to produce a focused laser; a workpiece formerhaving a complex shape to which the workpiece substantially conforms;and a positioner that makes an adjustment to keep the focused lasersubstantially focused on the workpiece as the positional relationshipbetween the workpiece former and the focused laser system changes to anoperating position that alters the distance between the workpiece andthe focused laser system due to the complex shape of the workpieceformer.
 2. The apparatus of claim 1, wherein the adjustment is made bymoving the workpiece former in a direction that changes the distancebetween the workpiece former and the focused laser system.
 3. Theapparatus of claim 1, wherein the adjustment is made by moving thefocused laser system in a direction that changes the distance betweenthe workpiece former and the focused laser system.
 4. The apparatus ofclaim 1 wherein the focused laser system further comprises a lens, andwherein the adjustment is made by moving the lens.
 5. The apparatus ofclaim 1, further comprising: a processor; a memory; and a set ofinstructions stored in the memory and executable by the processor tomove the workpiece former and to cause the positioner to make theadjustment based on data stored in the memory that correlates the changein focal length from the focused laser system to the workpiece caused bycarrier movement.
 6. The apparatus of claim 1, wherein the focused lasersystem comprises at least one mirror to move the focused radiation beamover the surface of the workpiece when the workpiece former is in anoperating position.
 7. The apparatus of claim 1, wherein the positionercomprises a position sensing device and a motor.
 8. The apparatus ofclaim 7, wherein the position sensing device is an optical sensor. 9.The apparatus of claim 7, wherein the position sensing device is anultrasonic sensor.
 10. The apparatus of claim 7, wherein the positioneroperates in real-time to make the adjustment using input from theposition sensing device.
 11. An apparatus for modifying a rubberworkpiece using a focused laser produced by a focused laser system, theapparatus comprising: a workpiece former, the workpiece former beingmovable to a plurality of operating positions and having a complex shapeto which the workpiece substantially conforms; and a positionercomprising a position sensing device; a processor; a memory; and a setof instructions stored in the memory and executable by the processor tomove the workpiece former to an operating position and to cause thepositioner to make an adjustment to the workpiece former to keep thefocused radiation beam substantially focused on the workpiece as theworkpiece former moves the workpiece former to an operating positionthat changes the distance between the workpiece and the focused lasersystem due to the complex shape of the workpiece, the adjustment beingmade using input from the position sensing device.
 12. A method ofmodifying a thin, flexible workpiece that conforms to a workpiece formerhaving a complex shape, the method using a focused laser produced by afocused laser system, the method comprising: changing the positionalrelationship between the focused laser system and the workpiece formerto establish a first operating position where the surface of theworkpiece is substantially at the focal length of the focused laserwhere the focused laser meets the workpiece; changing the positionalrelationship between the focused laser system and the workpiece formerto establish a second operating position that changes the distancebetween the workpiece and the focused laser system due to the complexshape of the workpiece former; and making an adjustment to keep thefocused laser substantially focused on the workpiece at the secondoperating position.
 13. The method of claim 12, wherein the adjustmentcomprises moving the workpiece former in a direction substantiallyparallel to an axis about which the focused laser is symmetric.
 14. Themethod of claim 12, wherein the adjustment comprises moving the focusedlaser system in a direction substantially parallel to an axis aboutwhich the focused laser is symmetric.
 15. The method of claim 12,wherein the adjustment comprises moving a lens in the focused lasersystem.
 16. The method of claim 12, further comprising: sensing thechange in distance between the workpiece and the focused laser systemcaused by changing the positional relationship between the focused lasersystem and the workpiece former from the first operating position to thesecond operating position, wherein the adjustment is made in response tothe sensed change in distance.
 17. The method of claim 12, furthercomprising: referring to data stored in a memory that correlates thechange in distance between the workpiece and the focused laser system tomotion from the first operating position to the second operatingposition, wherein the adjustment is made in response to the data storedin the memory.
 18. A method of producing a thin, flexible workpiece thatconforms to a workpiece former having a complex shape, the method usinga focused laser produced by a focused laser system, the methodcomprising the following steps in order: moving the workpiece formerinto liquid rubber; removing the workpiece from the liquid rubber andallowing the liquid rubber to dry on the workpiece; changing thepositional relationship between the focused laser system and theworkpiece former to establish a first operating position where thesurface of the workpiece is substantially at the focal length of thefocused laser where the laser meets the workpiece; activating thefocused laser system; changing the positional relationship between thefocused laser system and the workpiece former to establish a secondoperating position that changes the distance between the workpiece andthe focused laser system due to the complex shape of the workpieceformer; and making an adjustment to keep the focused laser substantiallyfocused on the workpiece at the second operating position.
 19. Themethod of claim 18, further comprising: deactivating the focused lasersystem before establishing the second operating position; and activatingthe focused laser system after the second operating position isestablished.
 20. The method of claim 18, wherein the focused lasersystem remains activated as the positional relationship between thefocused laser system and the workpiece former is changed.